Tack



June 12, 1923. 1,458,856,

s. sclsoREK TACK Filed Oct. A6. 1922 atto! nu;

IM/ventola Patented June 12, 1923.

Asie scrsoanx, cammina; Nw'jE'RSEyj i TACK.

Application filed October 6', 1922. Scrial'NO. 592,792.l

To' aZZ whom t may concern:

Be it known that I, SIG ScIsoREK, a citizen of the United States, residing at Newark, in the county of Essex and State of New Jersey, have invented new andl useful Improve-y ments in Tacks, of which the following is a specification.

This invention relates to improvements in thumb tacks and has for an object the provision of means whereby the tack may be lifted from the drawing board without inserting a knife or other sharp instrument beneath the tack edge with a possibility of mutilating or defacing the drawing paper.

Another object ofthe invention is the provision of a thumb tack having aknife edge, which will practically prohibit the insertion of a knife thereunder and which in addition,

will cause the T-square, or angle to ride over the head of the tack and'prevent mutilating or nicking the squared edge and reduce the danger of blurringthe drawing, should the square or angle strike the tack edge and accidentally contact'the wet lines of the drawing, as frequently occurs with the use of an ordinary tack.

With the above and other objects in view, the invention further includes the following novel features and details of construction, to be hereinafter more fully described, illus-v trated in the accompanying drawings and pointed out in the appended claims.

f Figure 1 is a plan View showing one form of tack.

Figure 2 is a `sectional view of the saine showing the use of the tack. n

Figure 3 is a plan view cfa modified vform of tack.

Referring in detail to the drawings, wherein like characters of reference denote corresponding parts, the reference character 1() indicates the head of a thumb tack, whose shank is shown at 11. The head 10 has its greatest thickness disposed centrally and` tapers outwardly to a knife-like edge 12, the said edge closely engaging the paper so as to cause the contacting T-square or angle to ride thereover without injury'to the edge of the instrument. This prevents an accidental pivoting of the instrument against the edge' of the tack, as frequently occurs with thev use of the ordinary thick edged tack, so that lia'- bility of blurring or smearing the lines of the drawing from this cause ispprevented. 55,v i

In addition, the formationof the. knife edge 12renders it practically impossible toins'ertv a knife or similar sharp instrument beneath f the tackedge when itis desired to remove 'the tack, so that mutilation or injury to the sur- 60 z face o-f the paper is also prevented. l For the purpose l,oi-"facilitating,the removal of a tack, the head 10-as shown in Figure 1 of the drawings, is provided upon opposite sides 'of its center with oppositelyf 65 disposed arcuate slots 13 whichextend en? tirely through the head of theftack and pro# .vide means for the. insertion of finger nails whereby the tack may be convenientlylifted. The head of the tack' isfthicker at its center l than elsewhere and the inner walls `13al of Y the slots 13 are inclined downwardly and` v inwardlyl toward th'eshankl 11. This causes, the edges lb'of the aforesaid walls'l?,Et to be so positioned with` respect to the edges 13c y of the adj acentwalls 13d of saidslots 13 that' thefinger nails -are guided into the slots and in proper engagement with the walls-13a. Through this construction, taken with the fact that the slots conform with the curva#I ture of the nails enablesfirm purchase of the nails against therhead of thetack and quick removal of the latter when desired. ,I

The .tack shown in AFigure 3 of the drawings kis similar in all respects to the tack just described, except that the slots l'iwhich i extend through the head upon opposite sides 'y of the center are arrangedin parallelism.

The invention herein described and shownl in the accompanying drawings provides a tack which is simple in construction, convenient and veficient in use and which may' be manufactured at a relatively small cost. In addition to eliminating danger of blur-k ring the lines of the drawing, due to the' apex .95

of a'triangle striking the edge ofA 'an ordinary tack, and the shank of the tack' is made relatively small and thin, so that the tend# i' ency is to pushV the tack inas the angle or square rides over thetop of the tack, instead of pushing it out through contact with the edge of an angle or square with-the edge of the .ordinary tack head; l `The hole made by the tack inthe drawing is thus materiallyV reduced in size. n y

The invention is susceptible of various changes in its form, proportions and minor details of constructionv and the right. is

hereinreserved to make such changes as tion tapering outwardly to define a knife properly fall within the scope of the apedge and having slots upon opposite sides pended claim. ofthe central portion, said slots extending N? Having described the inventiony What is entirely through the head, undhaving down- 5 claimed is:- v Wardly and inwardly tapered Walls.

A thumb tack having a plano-convex head ln 'testimony whereof I ax my signature. provided With a relatively thick central por- SIG SCISOREK. 

